.window_boundingBox {
    width: 500px;
    height: 300px;
    position: fixed;
    top: 100px;
    left: 50%;
    /*margin-left: -250px;*/
    border: 1px solid #000;
    box-shadow: 0 0 12px rgba(0, 0, 0, 0.5);
}

.window_alertBtn, window_confirmBtn, window_promptBtn {
    width: 100px;
    position: absolute;
    bottom: 15px;
    left: 50%;
    margin-left: -50px;
}

.window_header {
    background: #333;
    color: #fff;
    text-align: center;
    font-size: 20px;
    padding: 5px;
}

.window_body {
    padding: 10px;
}

.window_closeBtn {
    position: absolute;
    top: 0;
    right: 0;
    padding: 5px 10px;
    font-size: 20px;
    background: blue;
    color: #fff;
    cursor: pointer;
}

.window_mask {
    width: 100%;
    height: 100%;
    background: #fff;
    opacity: .3;
    position: absolute;
    top: 0;
    left: 0;
}

.window_footer {
    position: absolute;
    bottom: 0;
    padding-bottom: 10px;
    text-align: center;
    width: 100%;
}

.window_cancelBtn {
    margin-left: 20px;
}